The drawings and route descriptions contained in these materials serve only to show where most climbing parites go. On some climbs, the information is more precise than on others. If at some juncture this information confilicts with your judgement of the moment, recognize that it is only a guide; you should go where you think best. On the rock, your safety depends on your judgement.
There is no subsitute for personal instruction in rock climbing and climbing instruction is widely available. You should engage an instructor or guide to learn climbing safety techniques.